Unable to get IP from ISP

My WRT54G v2 is unable to get IP from my ISP. The internal LAN is working fine. It is just the WAN port that is giving me problem.
I suspect that the WAN port is defective after the episode with the lightning where my ADSL modem, a network card, phone when dead.
After i have my ADSL modem replaced, i have not luck at all in getting an IP. Can i uses on of the LAN port as the WAN port. so i can continue to uses the router. Or Should i got out and buy a new router. I have limited choice here, belkin, edimax, netgear and WRT54G v5. Does anyone know which one of these router is as versatile as my present Linksys router. Please can anyone out there help me.

You can redefine a LAN port as a WAN port in most of the 3rd party software. You'll probably need to read the associated firmware-of-choice's documentation to find out the specifics of how to do it. But it can definitely be done. (I've done it in OpenWRT.)

Yeah, you are on the right track - vlan is where it is - you need to put the port that you want to redefine as a WAN port ont the VLAN for WAN. That shoudl do the trick. Maybe take the bad port out, too, just in case it;s causing problems.

i was reading up on the forum about vlan. this is what i have done.
i telnet into my router. (I can't uses the ssh cos i don't have the password according to the router)
i type in the following command:
nvram set vlan0ports="1 2 3 5*"
nvram set vlan1ports="4 5"
nvram commit
reboot

i then telnet and type 'nvram show' to see that the it is set as such.
i connect my adsl modem onto port 4 of the router. i have internet access.

Just wondering did i miss out anything. cos from the forum there is other setting that they done which i don't quite understand. the only thing that make sense is the above.